Elastic Scattering of Electrons and Positrons from Rb and Cs atoms with relativistic effects

The elastic scattering of electrons and positrons with Rb and Cs atoms is investigated theoretically employing two different approaches: i) the relativistic Dirac partial wave analysis with a complex optical-potential model (OPM) [1] and ii) the nuclear structure approach (NSA) [2] for 1 eV ≤ Ei ≤ 1 GeV. The OPM incorporates the interaction of the projectile with both the nucleus and the bound target electrons, but the NSA retains only the projectile-nucleus interaction, without the shielding effect due to the bound electrons. An overlap region connecting properly both the low- and high-energy findings is established. Comparison with experimental and other theoretical findings shows the predictive power of our approach, which can easily handle heavier targets without much numerical efforts.

[1] Haque et. al, J. Phys. B 51, 175202 [2018].

 [2] T. W. Donnelly and I. Sick, Rev. Mod. Phys. 56, 461 (1984).